If I brought a smartphone, it would probably be torn down and reprocessed as blade edges. In one hand I'd carry a piece of scrap steel and in the other some mirrors and patterned silk. Stuffed in my pocket would be plasticized Google satellite maps.
The men and women of thirty thousand years ago would be quick learners. You can think of lots more if your goal is to kickstart the industrial revolution. I'm thinking of what the people would be ready to accept: Sharp edges for battle and things to make women look stunning to men.
Added: Probably the stuff you bring would be taken by force. If you don't want to try for the Number One position, perhaps a retreat to the forest with a personal survival kit would be wiser.
Update: Bring software not hardware. Language is software and it seems to have been upgraded maybe six thousand years ago to have a word for everything we see and do and to let us tell stories. No one can steal my language.